Liquid-depth-indicating device



H. W. KlNG LIQUID` DEPTH' INDICATING DEVICE Nov. 9 ,1926. l I 60,167

Filed April 1, 1920 31a/vantava ured. lThe Parenteel Nov. e, 1926.

UNITED STTES "r ric.'

HORACE W. KING, F ANN Annen", MICHIGAN, AssI'GNon 'ro KING-SEELEY ConroR'A- TIoN, or ANN Anson, MICHIGAN, A'ConPonArIoN oF MICHIGAN. l

LIQUID-DEPTH-INDICATING nn'vICn.

Application filed April 1, 1920. Serial No. 370,418.

The invention relates to devices for inditicularly to that type of device in which air under pressuredisplaces the 1i uid from an air chamber communicating with the body ofthe liquid at the full depth to be measressure of this air is equal to the hydrostatic head of the liquid down to its point of, communication with the air chamber, .so that a pressure gage to which .the pressure of the air is transferred can indicate by suitable graduations, the depthor the amount of the liquid. The invention is 'particularly applicable for indicating the `depth oramountof liquid fuel,such as O'asoline, ink automobile fuel tanks. One object ofthe invention, is the provision oftmeans for heating inclosed air to expand the same,

thereby producing a pressure suiicient. to

displace any liquid fuel from* the air chainber down to its point of communication with, the body of the li uid fuel. Another object is the provision o means for automatically lsupplying air to take the place of any o f that which escapesfrom the airchamber and passes up through the liquid fuel. Further objects of the invention reside in the novel arrangements and combination of parts as' more fully hereinafter set forth.

Inthe drawingsthe figure is a diagrammatic view partly in section of a constructionemb'odying my invention:

1 is an automobile fuel tank containing liquid fuel, such as asoline. 2 is a suitable air chamber prefera ly of cylindrical form within the tank and adjacent 'to its bottom,

this air chamber being providedwith a suitable aperture 3 in its side wall and near its bottom to place the interior of the air chamber -in communication with the liquidfuel. 4 lis-a substantially vertical tube having its lower end open and terminating insidel the air chamber 2 at substantially the sa'me level as the opening 3. 5 is a second substantially vertical tube preferably of larger diameter` than the tube 4 and having its lower end openend communicating vlwith the interior of the air chamber near the top thereof. This lower end is referably beveled so that when air is being orced through the tube 4' into the air chamber 2 to displace the liquid' fuel therefrom, the liquid in the tube 5 will more readily flow therefrom and be displaced by the air.

The upper ends ofth'e'tubes-4 and 5 are connected to the'coveror cap 6, which is re'- movably mounted upon the top of thetank 1.

of the tank 1, and 8 is a' nut threadedlyfeng gaging the cylindrical flanged member cylindrical flanged member.

' 10and 11 are nipples secured to the outer:

side of the cover or cap 6 and having aper-ptures 10 and 11 respectively',communicatingv with the tubes 4 and 5, respectively. 12 is a pipe having 4one end secured to and commu- "nica-tingwith the aperture 11 ofthe nipple -11 and the other end .secured'to and commu- -nicating with a' leg of a suitablepressure gage 13, such as a U-tube. v. For the pur ose of creating suflicient pres-l sure of air in t etube 4 to displace the-liquid 4fuel'from the air chamber 2 andtube 5, I'

have provided the followingconstruction: 14 'is a closedair tank vsecured against the 'exhaust manifold 15 of an internal combustion engine.=j .'16 is piping connected to and communicating with the nippleslO and 17 this latter nipple being secured to the closed tank 14 and communicating therewith.

, As thus far described, in' operation, upon starting the internal combustion engine, the

exhaust manifold 15 will become heated,

which in turn heats the closed -tank'14 and the air enclosed therewithin. The heating of this air increases the pressure thereof and consequently increases the pressure of.,

the air in the piping 16 and tube 4, so that the liquidfuel within the air chamber 2 and within the tube -5 4will be displaced therefrom and forced through the aperture 3 in the air chamber into the body of the liquid4 fuel.

The pressure-of the air in the lair chamber counterbalances the hydrostatic pressure exerted b the liquid fuel within the tank 1 above tl-Yi 13 having one leg in communication with the air chamber by means ofthe tube 5 and aperture 3 and thepressure gage noo - Asides of the container 18 near its to top of the tank 1.

pipe 12, indicates the depth or uantity of the liquid `fuel in the tank 1 an above the aperture 3. f

One disadvantage of this system, is that some of th`e air escapes through the aperture has` been once heated. For the purpose of 4maintaining approximately the same amounts of air in the system as the amount originally contained and when the system is at .original temperature, the closed Vvertical container 18 is provided iny the piping 1'6. In detail, this piping comprises the pipes 19 and 20, respectively connected to the. nipples 10 and 17 and the 'nipples 21 upon opposite 22 is a tube having' an open upper en communicating' with. the air .outside the .container .-18 and extending longitudinally within the same.v The lower end is open and terminates adjacent to the bottomdof t container. 23 is a suitable sealing liqui such as mercury, at the bottom of the container and surrounding the lowenend of the tube 22.

In operation when the motor is running the exhaust manifold 15 is heated and in turn heats theclosed air tank 14 thereby expanding the air in thetank and causing a portion of the air to pass through. the plpe 20, across the topV of the container 18, through pipe 19, tube 4 and into the air chamber 2. This air escapes from the lower end of the tube 4, dis laces the liquid fuel in the air chamber'an tube 5 and a portionescapes through. the'aperture 3 in the air chamber'. vW'hen the air is being expelled the pressure-in the closed tank 14, pipe 20, container 18, pipe 19, tube 4, and air chamber 2 is the pressure due to the depth of the liquid fuel in the tank l plus atmospheric pressure, there bein anl aperture 24 inthe he sealin liquid 23 in the container 18 rises in thetu e 22 a depth sufficient to balance this pressure.- The tube 5 andpipe 12 convey the pressure in the air chamber 2 to the pressure gage 13 which indicates the de th of the liquid fuel in thea' tank. When t e pressure `on the top of the* lliquid fuel in the tank is atmospheric, it is not necessary to have .a Ctube leading from th/e top of the tank to the other leg of the pressure gage. f

When Athe engine stopsv runningl the exhaust manifold 15 and air tank 14 are cooled, air then returns to the 'air' tank, this air being supplied through the tube 22, bubbling 11p-.through the sealing liquid.23 in the con- .'tainer 18 and passing through the pipe 20. `Whileair isreturning to the air tank/14,

liquid fuel enters through the aperture 3. into the air chamber v2 andeventually seals ythe lower end of the tube 4. This liquid fuel will rise in the tube 4 to apvelevation above the elevation of the liquid fuel in the tank,l 1,. depending upon the partial vacuum y in thel system, and balances the pressure of a column ofthe sealing liquid having a. height equal to the ditferenc in level between. the surface of the sea ing liquid 23 andthe bottom of the tube 22. .The nipples. 21 mounted on the container '18 are located at a sufficiently high elevation to prevent the entrance4 of the liquid fuel throu h the tube j 4 'and pipe 19 when the-'air tan 14 is recooling. l

From the above description it will be .readily seen that I have provided a device for indicating the depth or lamountv of a" ressure terminatingu the top of the air chamber, the gage. will give the. correct. reading regardless of whether the engine'is' running or at rest.

In general, it may be' stated that my device provides foi"automaticallyclearing air chamber .2 of liquid fuel whenever the mo tor starts and stops land at. the same time automatically corrects the reading of the gage. From experience I have found that such correction 1s necessary every vfew days.

What I claim as my invention is 1. The combinationwith an air chamber' communicating with a liquid atthe Lfull depth to be measured, of -an air conduit communicating with said airV chamber at one end and extending therefrom outside the liquid but beingclosed tothe atmosphere under normal working conditions, means for heating the air in said conduit to expand thc same and cause displacement' of the liquid in said .air chamber -.down to its point of .communicating `with a liquid at the full depth to be measured,.of a member adapted to s upply heat, a hollow air vessel communi eating at one point with said air chamber lo and extending thence adjacent to said heat supplying member, whereby the air in the vessel is heated and expanded t0` displace the liquid in said air chamber down. to .its point of communication with the liquid, a

communication with the liquid, a pressure v the latter.

pressure gage, means for transmitting the pressure of the air in said air chamber to said gage, and means for replacing in the air confining system including said chamber, vessel and pressure transmitting means any air escaping therefrom by said air chamber,4 ,Said means operating when said hollow an' vessel resumes its original temperature.

3. The combination with an air chamber `tween lsaid tank and tube, a tube communicating Vwith the air outside said container and extendlng theremto, means for sealing the inner end of said tube during the time the air in said tank is at a temperature above the original temperature, `said means permitting of the inward flow of the air from outside said container to replace any air escapingfrom said air chamber, when the air.-

in said tank recools to its original temperature, and a pressure indicator communicating with said'air chamber.

4. The combination with a tank containing liquid fuel, of an exhaust manifold, an air chamber in Asaid tank communicating with the liquid fuel therein at the full depth to be measured, a vertical tube having its lower end opening into said air chamber at substantially the level of the point of communication of said air chamber with .the li uid fuel, a closed air tank adjacent to sa-id e aust manifold, a closed container, pipes leadin from said tube and closed air tank to sai container, a vertical tube extending within said container and having its upper end open to the air outside said container and its lower end open and terminating ad-v jacent to the bottom of said container, a seallng liquid Awithin said container and surrounding the lower end 'of said tube therewithin, and a pressure gage communicating with said air chamber near the upper end of 5. In an apparatus of the class described,

the combination of a liquid container, pressure responsive vmeans for indicating the Vdepth of liquid therein, a pressure transmitting conduit extending from said means to the container and provided with an opening whereby liquid from the container may enter it at a point below level of liquid in said container and temperature .responsive means for introducing air into said conduit. 6.0 I,

6. In an apparatus ofthe class described, the combination of a liquid container, pressure responsive means lfor indicating the 'depth of liquid therein, a' pressure transmitting conduit extending from said means. to the container and provided with an opening whereby liquid from the container may enter it at a point below level of liquid in said container, said' conduit being also enlarged 'at itsl liquid receiving end, and temperature responsive means for supplying air to said enlarged portion to lower the level of liquid therein.

. 7. In an apparatus of the-classdescribed, the combination of a liquid container, pressure responsive means for indicating the depth lof liquid therein, a pressure transmitting conduit extending fromsaid means to the container and provided with an openingl whereby liquid from the container may enter it at a point belowlevel of liquid in said container, and means forming an air confining chamber connected with said conduit at a pointbelow a level of liquid therein, whereby expansion 'of air in said chamber will cause a portion of said air to be discharged into the conduit.

8. In an apparatus of the class described, the combination of a liquid container, pressure responsive means for indicating the depth of liquid therein, a pressure transmitting condult extending from saidmeans to the container and provided with an open- 'ing whereby liquid from the container may enter it at a point below level of liquid in said container, .and means forming an air confining chamber connected with said conduit at a point below a level of liquid therein, where y expansion of air in said chamber will cause a lportion of said air to be discharged into the conduit, and means permitting entrance of air -to said chamber.

9. Inan apparatus of the class described, the combination of a liquid container, pressure responsive means for indicating the depth of liquid therein, a pressure trans'- mitting conduitv extending from said means to the container and rovidedv with an open- Ving whereby liquid rom the container may enter it at a point below level of liquid in said container, means forming anair confv lining chamber connected with said conduit at a Apoint below a level ofliquid therein, whereby expansion of air in said chamber will cause a'portionvof said air to,be discharged into the conduit,I and a one-way valve for admission of air to said chamber. 10. lThe combination with amotor vehicle fuel tank containing liquid fuel, said tank being normally open to atmospheric pressure and having aclosable enlarged opening'in vthe upper wall thereof, of an enlarged air chamber insertable downwardly in thesaid tank through said enlarged opening and extending into the liquid fuel and positioned near the bottom of said tank, said air chambenhaving a closed upper wall and an opening below said upper wall for placing the interior of said chamber in communication with the liquid fuel in said tank, e, a pressure transmitting tube communicating 130 veith the upper lportion of said air cham, ber, a pressure gauge connected to and ,comIA municating with ther interiorof said pres*- sure transmitting tube, means for replenishing the* air in said air chamber including a second tube extending from above the normal surface of the liquid fuel and havlng its lowery'end opening directly into the air "chamber, a cover for closing the enlarged opening in the 'tank through which said "chamber is inserted, `said cover being supported upon said tank and carrying said tubes and chamber as a unit, and means for producing -iioWv of air through said second Atube directly into said air chamber.

In testimony whereof I axfmy signature.

HQRACE W. KING-` 

